Writing instrument



FIG. 1 is a left side elevational view of a writing instrument showing my new design in an exploded condition;

FIG. 2 is a rear elevation view thereof with the cap and barrel joined;

FIG. 3 is a left side elevation view thereof with the cap and barrel joined;

FIG. 4 is a front elevation view thereof with the cap and barrel joined;

FIG. 5 is a right side elevation view thereof with the cap and barrel joined;

FIG. 6 is a top view thereof with the cap and barrel joined; and,

FIG. 7 is a bottom view thereof with the cap and barrel joined. 

The ornamental design for a writing instrument, as shown and described. 